Valve Steam before 2021-04-17, when a Source engine game is installed, allows remote…
Priority MEDIUM 45CWE-120Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- Low
- User interaction
- Required
- Attack complexity
- Low
- Impact type
- Code execution
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- No fix listed
Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-120 and the CVSS impact.
Summary
Valve Steam before 2021-04-17, when a Source engine game is installed, allows remote authenticated users to execute arbitrary code because of a buffer overflow that occurs for a Steam invite after one click.
Why it matters now
EPSS 0.03533 89th percentileScored 2026-11-07
Public exploit Yes 2 exploit referencesTagged by NVD
Fix No fix listed No fixed version in the sources yet
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| — | — | all versions | — | No fix listed | CNA |
- — Vendor— Affected all versions Fixed in — No fix listed CNA
CPE configurations NVD · 1
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:valvesoftware:steam_client:*:*:*:*:*:*:*:* | up to 2021-04-10 | Vulnerable | Valvesoftware |
- cpe:2.3:a:valvesoftware:steam_client:*:*:*:*:*:*:*:* Versions up to 2021-04-10 Vulnerable ·Valvesoftware
Remediation
No fixed version listed by the sources yet.
Timeline
- 2026-10-02 Threatist record created from CVE-2021-30481
- 2026-10-03 Alias added: GHSA-3jx7-82j9-5prx
References
More Valvesoftware Steam Client vulnerabilities
- TI-2020-12227 An issue was discovered in Valve Steam Client 2.10.91.91. CVSS 3.1HIGH 7.8
- TI-2019-12806 Valve Steam Client before 2019-09-12 allows placing or appending partially controlled… CVSS 3.1HIGH 7.8
- TI-2019-11419 Valve Steam Client for Windows through 2019-08-16 allows privilege escalation (to NT… CVSS 3.0HIGH 7.8
- TI-2015-06635 Valve Steam 2.10.91.91 uses weak permissions (Users: read and write) for the Install… CVSS 2.0HIGH 7.2
- TI-2019-11420 Valve Steam Client for Windows through 2019-08-20 has weak folder permissions, leading to… CVSS 3.0HIGH 7.0
- TI-2019-10955 In Valve Steam Client for Windows through 2019-08-07… CVSS 3.0MEDIUM 6.6
Sources
- CVE-2021-30481 · CVE Program
- CVE-2021-30481 · NVD
- FIRST EPSS
- GHSA-3jx7-82j9-5prx · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences